Abstract:

Objective To investigate the frequency of CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Treg)in peripheral blood of patients with chronic hepatitis B (CHB)and its significance in the hepatitis B virus (HBV)infection. Methods The frequencies of CD4⁺CD25⁺Foxp3⁺Treg in peripheral blood from 86 CHB patients,30 acute hepatitis B (AHB)patients and 30 healthy subjects were determined by flow cytometry.The correlations of HBV DNA loads with CD4⁺CD25⁺Foxp3⁺ Treg frequency and the frequency of CD4⁺CD25⁺Foxp3⁺ Treg after therapy with different therapeutic effects were analyzed respectively.CD4⁺CD25⁺Foxp3⁺ Treg frequencies among mild,moderate and severe active CHB patients were compared respectively. Results The percentages of CD4⁺CD25⁺Foxp3⁺ Treg in CHB patients,AHB patients and healthy subjects were 2.56%±1.12%,1.39%±0.68% and 1.45%±0.76%, respectively.The percentage in CHB patients was higher than those in AHB patients and healthy subjects (P<0.05),and there was no statistical significance between the percentages of AHB patients and healthy subjects (P>0.05).The percentages of CD4⁺CD25⁺Foxp3⁺ Treg among mild,moderate and severe active CHB patients had no statistical significance (P＞0.05).The levels of alanine aminotransferase (ALT)in CHB patients,AHB patients and healthy subjects were 285.6±168.3,(780.9±432.6) and (23.2±6.7) U/L, respectively.The levels of ALT in CHB patients and AHB patients were higher than that in healthy subjects(P<0.05).The level of ALT in CHB patients was lower than that in AHB patients(P<0.05).The frequency of CD4⁺CD25⁺Foxp3⁺ Treg was not correlated with the level of ALT (r=0.11,P>0.05).The HBV DNA loads in CHB patients,AHB patients and healthy subjects were (5.2±1.8)log₁₀copies/mL,(7.2±1.8)log₁₀copies/mL and negative respectively.The HBV DNA load in AHB patients was higher than that in CHB patients(P<0.05).There was a positive correlation between CD4⁺CD25⁺Foxp3⁺ Treg frequency and HBV DNA logarithm(r＝0.30,P＜0.05).CD4⁺CD25⁺Foxp3⁺ Treg frequency decreased obviously after anti-viral therapy in the patients with obvious good therapeutic effect,and it was lower than that in the patients with poor therapeutic effect (P<0.05). Conclusions The increase of CD4⁺CD25⁺Foxp3⁺ Treg in CHB patients plays an active role in chronic HBV.The regulation and control of function and amount of CD4⁺CD25⁺Foxp3⁺ Treg may provide a new therapy for CHB.

Key words: CD4⁺CD25⁺Foxp3⁺ regulatory T cell, Chronic hepatitis B, Therapeutic effect